Event Notification Report for April 21, 1999
U.S. Nuclear Regulatory Commission Operations Center Event Reports For 04/20/1999 - 04/21/1999 ** EVENT NUMBERS ** 35609 35610 35611 +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35609 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: POINT BEACH REGION: 3 |NOTIFICATION DATE: 04/20/1999| | UNIT: [1] [2] [] STATE: WI |NOTIFICATION TIME: 15:39[EDT]| | RXTYPE: [1] W-2-LP,[2] W-2-LP |EVENT DATE: 04/20/1999| +------------------------------------------------+EVENT TIME: 13:53[CDT]| | NRC NOTIFIED BY: R. HASTING |LAST UPDATE DATE: 04/20/1999| | HQ OPS OFFICER: JOHN MacKINNON +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |MELVYN LEACH R3 | |10 CFR SECTION: | | |AOUT 50.72(b)(1)(ii)(B) OUTSIDE DESIGN BASIS | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ |1 N Y 100 Power Operation |100 Power Operation | |2 N Y 100 Power Operation |100 Power Operation | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | Postulated fire in the Auxiliary Feedwater room could affect diesel power to | | Safe Shutdown Equipment. | | | | For a postulated fire in the north half of the Auxiliary Feed Water (AFW) | | Pump Room, the G-0l Diesel Generator is relied upon to provide emergency | | diesel power to Safe Shutdown Equipment. Without the fuel oil pump, there | | will only be enough fuel in the day tanks to run the diesel for 4 hours. | | This will not support maintaining Hot Shutdown of the units. The G-02 Diesel | | Generator will not be available due to loss of ventilation to the G-02 | | Diesel Room for room exhaust fan cables being located in the north half of | | the AFW Pump Room. The G-03 or G-04 Diesel Generators will not be available | | due to the potential loss of control circuitry and power feeds to | | transformers 1X-14 and 2X-14 being located in the north half of the AFW Pump | | Room as well. | | | | The primary significance of this scenario is that in order to insure the | | proper Appendix R equipment is available for a fire in the north half of the | | AFW Pump Room the 1A-05 bus must have power. Provisions must be made to | | maintain G-01 as that supply source or qualify another source such as G-05 | | Gas Turbine. Without G-01 availability, this places the plant outside of | | design basis for Appendix R. | | | | Compensatory actions at this time are twice per shift (8 hour shift) | | Appendix R fire inspections. | | | | The licensee is looking into using the Gas Turbine, G-05, or locally | | starting the G-03 Diesel Generator. | | | | The NRC Resident Inspector will be informed of this notification by the | | licensee. | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35610 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: COOK REGION: 3 |NOTIFICATION DATE: 04/20/1999| | UNIT: [1] [2] [] STATE: MI |NOTIFICATION TIME: 18:17[EDT]| | RXTYPE: [1] W-4-LP,[2] W-4-LP |EVENT DATE: 04/20/1999| +------------------------------------------------+EVENT TIME: 16:14[EDT]| | NRC NOTIFIED BY: BRIAN MUTZ |LAST UPDATE DATE: 04/20/1999| | HQ OPS OFFICER: DICK JOLLIFFE +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |MELVYN LEACH R3 | |10 CFR SECTION: | | |AIND 50.72(b)(2)(iii)(D) ACCIDENT MITIGATION | | | | | | | | | | | +-----+----------+-------+--------+-----------------+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ |1 N N 0 Cold Shutdown |0 Cold Shutdown | |2 N N 0 Cold Shutdown |0 Cold Shutdown | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | - Aux Bldg Vent Systems may not meet their safety and accident mitigation | | function during accident conditions - | | | | The licensee reviewed the Auxiliary Building Ventilation Systems as part of | | the Expanded System Readiness Reviews (ESRRs). The scope of the ventilation | | review included the Engineered Safety Features (ESF) Ventilation, known as | | Auxiliary Equipment Subsystem (AES), which is the focus for this report. | | | | The AES safety and accident mitigation function is to provide sufficient | | cooling to the general areas and safety related equipment rooms required to | | operate during accident conditions for multiple safety related systems, | | including Component Cooling Water System, Containment Spray System, Residual | | Heat Removal System, Charging System, and Safety Injection System. | | | | As a result of the ESRR, it has been concluded that currently there is | | insufficient assurance that the AES is capable of meeting its safety and | | accident mitigation function for temperature control of the Auxiliary | | Building in its present configuration. This conclusion is based on | | significant errors that were identified in ventilation related temperature | | calculations for the Auxiliary Building, combined with the small margin that | | previously existed between calculated results and design requirements, such | | that there is little assurance of adequate auxiliary building room cooling | | for ESF equipment. In addition, the AES dampers are not single failure | | proof (as previously reported) and the system lacks missile protection | | between trains. | | | | Both units are currently in Operational Mode 5 (Cold Shutdown). Priority | | evaluation of these issues, including determination of the need for physical | | modifications, is ongoing and will be resolved prior to startup of the | | units. | | | | The licensee notified the NRC Resident Inspector. | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ |Power Reactor |Event Number: 35611 | +------------------------------------------------------------------------------+ +------------------------------------------------------------------------------+ | FACILITY: LIMERICK REGION: 1 |NOTIFICATION DATE: 04/20/1999| | UNIT: [1] [] [] STATE: PA |NOTIFICATION TIME: 19:21[EDT]| | RXTYPE: [1] GE-4,[2] GE-4 |EVENT DATE: 04/20/1999| +------------------------------------------------+EVENT TIME: 18:32[EDT]| | NRC NOTIFIED BY: RAY McKINLEY |LAST UPDATE DATE: 04/21/1999| | HQ OPS OFFICER: DICK JOLLIFFE +-----------------------------+ +------------------------------------------------+PERSON ORGANIZATION | |EMERGENCY CLASS: N/A |MOHAMED SHANBAKY R1 | |10 CFR SECTION: |CURT COWGILL R1 | |ACCS 50.72(b)(1)(iv) ECCS INJECTION |RANDY BLOUGH R1 | |ARPS 50.72(b)(2)(ii) RPS ACTUATION |DON FLOREK R1 | |AESF 50.72(b)(2)(ii) ESF ACTUATION |ART BURRITT SRI | | |WILLIAM BATEMAN NRR | +-----+----------+-------+--------+-----------------+--------+-----------------+ |UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE | +-----+----------+-------+--------+-----------------+--------+-----------------+ |1 A/R Y 100 Power Operation |0 Hot Shutdown | | | | | | | +------------------------------------------------------------------------------+ EVENT TEXT +------------------------------------------------------------------------------+ | - AUTO REACTOR SCRAM FROM 100% POWER DUE TO LOSS OF MAIN FEEDWATER; ECCS | | INJECTION - | | | | AT 1832 ON 04/20/99, WITH UNIT 1 AT 100% POWER, ALL EIGHT CONDENSATE SYSTEM | | DEEP BED DEMINERALIZER OUTLET MOTOR OPERATED VALVES FAILED CLOSED POSSIBLY | | DUE TO A COMPUTER MALFUNCTION. THE DEMINERALIZER BYPASS VALVES TRIPPED DUE | | TO THERMAL OVERLOADS AND FAILED TO OPEN, CAUSING ALL THREE STEAM DRIVEN MAIN | | FEEDWATER PUMPS TO TRIP. THE REACTOR VESSEL WATER LEVEL DROPPED FROM A | | NORMAL LEVEL OF +35 INCHES TO +12.5 INCHES, CAUSING THE REACTOR TO | | AUTOMATICALLY SCRAM FROM 100% POWER DUE TO LOW REACTOR VESSEL WATER LEVEL. | | ALL CONTROL RODS INSERTED COMPLETELY; HOWEVER, ROD #30-39 INSERTED SLOWLY. | | NO SAFETY/RELIEF VALVES LIFTED. STEAM IS BEING DUMPED TO THE MAIN | | CONDENSER. | | | | REACTOR VESSEL WATER LEVEL FURTHER DROPPED TO -38 INCHES, CAUSING THE HIGH | | PRESSURE COOLANT INJECTION (HPCI) AND THE REACTOR CORE ISOLATION COOLING | | (RCIC) SYSTEMS TO ACTUATE AND INJECT INTO THE REACTOR VESSEL. THE REDUNDANT | | REACTIVITY CONTROL SYSTEM INITIATED TO TRIP THE CIRCUIT BREAKERS FOR THE | | REACTOR RECIRCULATION PUMPS. PRIMARY CONTAINMENT ISOLATION SYSTEM GROUPS | | 1B, 2A, 2B, 2C, 3, 6A, 6B, 6C, 7B, AND 8B ISOLATED. THE DIVISION 'A' | | ATWS/RPT CIRCUIT BREAKER FOR THE 'A' RECIRC MOTOR GENERATOR SET FAILED TO | | TRIP, AS REQUIRED. SMOKE WAS OBSERVED TO BE COMING FROM THE BREAKER. THE | | BREAKER WAS MANUALLY TRIPPED FROM THE CONTROL ROOM AND THE SMOKING STOPPED. | | THE 'A' AND 'B' RECIRC MOTOR GENERATOR SET DRIVE MOTOR CIRCUIT BREAKERS ALSO | | FAILED TO TRIP ON THE 13 kV BUS FAST TRANSFER. THE BREAKERS WERE MANUALLY | | TRIPPED. | | | | REACTOR VESSEL WATER LEVEL DROPPED TO A LOW LEVEL OF -75 INCHES ABOUT 40 | | SECONDS INTO THE EVENT (TOP OF ACTIVE FUEL IS -161 INCHES). THE HPCI AND | | RCIC SYSTEMS RECOVERED REACTOR VESSEL WATER LEVEL TO +25 INCHES, AT WHICH | | TIME CONTROL ROOM OPERATORS MANUALLY SECURED THE HPCI SYSTEM. THE RCIC | | SYSTEM IS MAINTAINING REACTOR VESSEL WATER LEVEL AT +25 INCHES WITH REACTOR | | PRESSURE AT 875 PSIG AT AN INJECTION RATE OF 300 GPM. | | | | PLANT OPERATORS ENCOUNTERED A PROBLEM WITH THE AUXILIARY STEAM SYSTEM AND | | THE MECHANICAL VACUUM PUMP. THEY MANUALLY CLOSED THE MAIN STEAM ISOLATION | | VALVES. THEY ARE CONTROLLING REACTOR VESSEL WATER LEVEL WITH THE RCIC | | SYSTEM AND REACTOR COOLANT SYSTEM PRESSURE WITH THE HPCI SYSTEM. | | | | UNIT 1 IS STABLE IN OPERATIONAL CONDITION 3 (HOT SHUTDOWN) AND COOLING DOWN | | TO COLD SHUTDOWN. PRIMARY CONTAINMENT PARAMETERS ARE NORMAL. THERE WAS NO | | RELEASE OF RADIOACTIVE MATERIAL. RELEASE RATES ARE NORMAL. THIS EVENT HAD | | NO IMPACT ON UNIT 2 WHICH IS IN OPERATIONAL CONDITION 5 IN A REFUELING | | OUTAGE. | | | | THE LICENSEE NOTIFIED THE NRC RESIDENT INSPECTOR AND IS INVESTIGATING THIS | | EVENT. THEY PLAN TO ISSUE A PRESS RELEASE. | | | | *** UPDATE ON 4/21/99 @ 0418 BY HUNTER TO GOULD *** | | | | THE REACTOR IS IN OPCON 3 AT 350 PSIG CONTINUING TO COLD SHUTDOWN. | | CONDENSER VACUUM IS BEING REESTABLISHED IN ORDER TO RE-OPEN THE MSIVs AND | | SECURE HPCI FROM PRESSURE CONTROL MODE. FEEDWATER SYSTEM IS BEING | | REPRESSURIZED TO REESTABLISH NORMAL FEED AND SECURE RCIC FROM LEVEL CONTROL | | MODE. | | | | ALSO THE "1A" AND "1B" MG SET DRIVE MOTOR BREAKERS DID NOT TRIP DURING THE | | TRANSIENT SINCE PLANT LOADS WERE PREVIOUSLY TRANSFERRED BY A REACTOR | | OPERATOR PRIOR TO THE TURBINE TRIP. THE BREAKERS, THEREFORE, OPERATED AS | | DESIGNED. | | | | THE RESIDENT INSPECTOR WAS NOTIFIED. | | | | THE REG 1 RDO(SHANBAKY) WAS NOTIFIED. | +------------------------------------------------------------------------------+
Page Last Reviewed/Updated Thursday, March 25, 2021
Page Last Reviewed/Updated Thursday, March 25, 2021